Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) said: A man came to the Prophet (peace and blessings be upon him) from Yemen and said: O Messenger of Allah, I have left my homeland. The Messenger of Allah (peace and blessings be upon him) said: "You have left shirk, but (what remains) is jihad. Do you have any relative in Yemen?" He said: My parents. He (peace and blessings be upon him) asked: "Have they given you permission?" He said: No. He (peace and blessings be upon him) said: "Go back and ask their permission. If they permit you, then wage jihad; otherwise, treat them well."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب السير / 17831